Safety Study of Quadrivalent Subunit Influenza Vaccine in People Aged 3 Years and Older

Overview

This study evaluates the safety of the quadrivalent subunit influenza vaccine following its post-marketing widespread use in individuals aged 3 years and older, aiming to assess the occurrence of very rare adverse reactions (with an incidence rate of \<0.01%).

This is a large-scale, multicenter, open-label, single-arm, non-controlled real-world safety observational study following influenza vaccination. It is designed to assess the occurrence of very rare adverse reactions (incidence \<0.01%) following vaccination with a quadrivalent influenza subunit vaccine and to demonstrate its superior safety profile. A total of 42,881 participants aged 3 years and above were enrolled. Each received a single 0.5 ml dose of the quadrivalent influenza subunit vaccine. Safety monitoring included immediate observation for 30 minutes post-vaccination and systematic surveillance over the subsequent 28 days. Data on adverse events (AEs) and serious adverse events (SAEs) were collected during two time intervals: from 30 minutes to 7 days (inclusive) and from 8 to 28 days (inclusive) after vaccination. Any newly identified adverse reactions during the study period were also recorded.

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Eligibility

Locations (8)

Outcomes